I'm not sure whether Deluge is just one treatment, or whether it's Patagonia's name for any DWR they apply.
Certainly, some Deluge is a silicone encapsulation, like EPIC (which Pata used to use under their name EnCapSil).
I have a few Patagonia items all with Deluge; Stretch Zephyr, Supercell, Core Skin, Mixmaster & Dragonfly.
The item I've used most is the Supercell, as a lightweight work cycling jacket. Its DWR seems to have lasted about as long as any other. I'm not sure that it's been markedly better than others.
The DWR on the Stretch Zephyr is remarkable, though; the water really beads incredibly well. I can't comment on the longevity, as I have so many shelled micropile jackets...
The Core Skin and Mixmaster are both PowerShield, and the DWR seems effective, although I mostly use them for skiing, so they don't often get exposed to a lot of water.
I have heard from a reliable source that it's best never to do a detergent wash, as it doesn't seem to be possible to recover the situation with a soap wash. That was with a Dragonfly.
Frankly, I'd not be particularly swayed by the DWR; I'd go for fit, function and price. After-market DWR treatments are pretty easy to use.